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Detective Conan

16 year-old Kudo Shinichi, a famous High school detective, treats his friend, Mori Ran to a theme park named Tropical Land. After solving a murder case that occured on the same day, Shinichi notices and tails two people in black. However, one of them notices Shinichi and knocks him out. Instead of killing him, they gave him an untested poison that was supposed to kill him yet leave no traces. However, instead of killing him, it shrunk him into a 8 year old boy. Shinichi now goes under the name Edogawa Conan.